Can't find NSEC3 for empty nonterminal

Oct 4 08:19:46 fou ods-signerd: signer engine started
Oct 4 08:19:46 fou ods-signerd: unable to open file nz.state for reading: No such file or directory
Oct 4 08:19:48 fou ods-auditor[13373]: Auditor started
Oct 4 08:19:48 fou ods-auditor[13373]: Auditor starting on nz
Oct 4 08:19:48 fou ods-auditor[13373]: Auditing nz zone : NSEC3 SIGNED
Oct 4 08:19:48 fou ods-auditor[13373]: Can't find NSEC3 for empty nonterminal dns.net.nz (should be 3ge8vaothoo9gh6o53auhhpts4ra01qo.nz)
Oct 4 08:19:48 fou last message repeated 5 times
Oct 4 08:19:48 fou ods-auditor[13373]: Can't find NSEC3 for empty nonterminal net.nz (should be 76g4um7rj36p4mam1jrtvopmugodvk39.nz)
Oct 4 08:19:48 fou last message repeated 5 times
Oct 4 08:19:48 fou ods-auditor[13373]: Finished auditing nz zone
Oct 4 08:19:48 fou ods-signerd: task [audit zone nz] failed